Now, to restore course category do this:

Now, to restore course category do this:
- Check if (category_id, category_name) exists.
- Check if (category_name) exists.
- Check if category_id = 1 exists.
- Create a new, initially invisible category withe the info in backup-file.

This solves a issue when restoring to a new course and category_id 1
had been removed !!